A difficult part of tree removal is the disposal of the stump after the tree has been cut down. One common method is to simply uproot the stumps and dispose of them. However, uprooting the stumps is not always possible or economical particularly where there are only a few stumps.
Another method of removing stumps is by cutting them away with a machine called a stump grinder. This machine utilizes a rotating vertically oriented wheel having cutting teeth mounted around the circumference of the wheel. The stump grinder tears away the stump by passing across it several times until they have completely eliminated the stump.
As can be expected, grinding down these tree stumps causes rapid deterioration of the sharp edges of the cutting teeth on the stump grinding tool; particularly when the stumps as they often are, are extremely hard woods. For this reason frequent resharpening of the cutting teeth is required. This, however, presently is a difficult and time consuming task.
Stump grinding wheels and teeth have sixteen and sometimes many more cutting teeth on them, eight on either side extending radial outward and bending slightly away from the plane of the wheel. Presently the teeth are removed from the wheel and resharpened on a grinding wheel and replaced. Each tooth is comprised of a elongate shaft or shank terminating in an angle portion or head, having a cutting face or insert brazed or silver soldered onto the head. A carbide or hardened steel insert is used for the cutting face to increase the life of the cutting teeth.
Each tooth is held on the circumference of the rotating wheel by a clamping plate which clamps and bolts the tooth to the wheel. The head and cutting face of the tooth extend outward beyond the peripheral or circumferential edge of the wheel.
Each tooth is held on the wheel by the shank fitting a socket formed by the clamping plate which is bolted to the wheel and clamped down tightly. After a period of use the bolt and clamp becomes extremely clogged and it is extremely difficult to remove the teeth. Sometimes they need to hammer or even cut the clamping plate off to remove and replace, or resharpen the teeth.
In some cases the wheels of the stump grinding machines can be as much as four feet in diameter and have one hundred and fifty sockets for receiving cutting teeth. Removal of all the teeth to sharpen them at a shop can, in some cases, take several days. Thus, there presently is no convenient method for quickly sharpening stump grinder teeth without removing them completely from the machine. Unfortunately removing each tooth for resharpening is a difficult, time consuming and expensive process.
It is therefore one object of the present invention to provide a sharpening apparatus which can sharpen stump grinder teeth without removing them from the machine.
Yet another object of the present invention is to provide a sharpening apparatus which can clamp directly to stump grinding teeth for automatically sharpening them.
Still another object of the present invention is to provide a sharpening apparatus that can be clamped onto a stump grinding tooth and can easily be brought into in proper alignment for grinding and sharpening the tooth edge.
Still another object of the present invention is to provide a sharpening apparatus which can sharpen teeth on a stump grinder at the site without removing the cutting teeth from the machine.